java - 组织.json.JSONException : End of input at character 0

Question

我已经坚持了一段时间。根本无法弄清楚出了什么问题。一双新鲜的眼睛会很有帮助。我不断收到 org.json.JSONException: End of input at character 0 of 并且无法弄清楚。

我的 JSONParser

 public JSONObject makeHttpRequest(String url, String method,
        List<NameValuePair> params) {

    // Making HTTP request
    try {

        // check for request method
        if(method == "POST"){
            // request method is POST
            // defaultHttpClient
            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);
            httpPost.setEntity(new UrlEncodedFormEntity(params));

            HttpResponse response = httpClient.execute(httpPost);
            String responseBody = EntityUtils.toString(response.getEntity());
            //HttpEntity httpEntity = httpResponse.getEntity();
            //is = httpEntity.getContent();
           JSONArray jsArray = new JSONArray(responseBody);
           JSONObject js = jsArray.getJSONObject(0);
           String returnvalmsg = js.getString("message");
           String returnvalsucc = js.getString("success");

        }else if(method == "GET"){
            // request method is GET
            DefaultHttpClient httpClient = new DefaultHttpClient();
            String paramString = URLEncodedUtils.format(params, "utf-8");
            url += "?" + paramString;
            HttpGet httpGet = new HttpGet(url);

            HttpResponse httpResponse = httpClient.execute(httpGet);
            HttpEntity httpEntity = httpResponse.getEntity();
            is = httpEntity.getContent();
        }          

    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    } catch (ClientProtocolException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
   // } catch (JSONException e) {
        // TODO Auto-generated catch block
        //e.printStackTrace();
    } catch (JSONException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

    try {
        BufferedReader reader = new BufferedReader(new InputStreamReader(
                is, "iso-8859-1"), 8);
        StringBuilder sb = new StringBuilder();
        String line = null;


        while ((line = reader.readLine()) != null) {
            sb.append(line + "\n");
        }
        is.close();
        json = sb.toString();

    } catch (Exception e) {
        Log.e("Buffer Error", "Error converting result " + e.toString());
    }

    // try parse the string to a JSON object
    try {
        jObj = new JSONObject(json);
    } catch (JSONException e) {
        Log.e("JSON Parser", "Error parsing data " + e.toString());
    }

    // return JSON String
    return jObj;

  }
}

Activity

btnRegisterfine.setOnClickListener(new View.OnClickListener() {

                             @Override
                            public void onClick(View view) {
                                // creating new product in background thread
                                new CreateNewFine().execute();
                            }


                      });
    }

                      /**
                         * Background Async Task to Register Fine
                         * */
                        class CreateNewFine extends AsyncTask<String, String, String> {

                            /**
                             * Before starting background thread Show Progress Dialog
                             * */
                            @Override
                            protected void onPreExecute() {
                                super.onPreExecute();
                                pDialog = new ProgressDialog(Finecalc.this);
                                pDialog.setMessage("Registering Fine..");
                                pDialog.setIndeterminate(false);
                                pDialog.setCancelable(true);
                                pDialog.show();
                            }

                            /**
                             * Registering Fine
                             * */
                            protected String doInBackground(String... args) {
                                String driver = inputDriver.getText().toString();
                                String licencenum = inputLicence.getText().toString();
                                String officer = inputOfficer.getText().toString();
                                String speed = inputSpeed.getText().toString();
                                String fine= FineAppl.getText().toString();
                                String category = inputCategory.getText().toString();


                                // Building Parameters
                                List<NameValuePair> params = new ArrayList<NameValuePair>();
                                params.add(new BasicNameValuePair("driver", driver));
                                params.add(new BasicNameValuePair("licencenum", licencenum));
                                params.add(new BasicNameValuePair("officer", officer));
                                params.add(new BasicNameValuePair("speed", speed));
                                params.add(new BasicNameValuePair("fine", fine));
                                params.add(new BasicNameValuePair("category", category));

                                // getting JSON Object
                                // Note that create product url accepts POST method
                                JSONObject json = jsonParser.makeHttpRequest(url_create_fine,
                                        "POST", params);

                                // check log cat fro response
                                Log.d("Create Response", json.toString());

                                // check for success tag
                                try {
                                    int success = json.getInt(TAG_SUCCESS);

                                    if (success == 1) {
                                        // successfully Registered Fine
                                        //Intent i = new Intent(getApplicationContext(), Finecalc.class);
                                        //startActivity(i);
                                        registerFine.setText("DONE");
                                        // closing this screen
                                        finish();
                                    } else {
                                        // failed to Register Fine
                                    }
                                } catch (JSONException e) {
                                    e.printStackTrace();
                                }

                                return null;
                            }

                            /**
                             * After completing background task Dismiss the progress dialog
                             * **/
                            protected void onPostExecute(String file_url) {
                                // dismiss the dialog once done
                                pDialog.dismiss();
                            }

                        }

我的 PHP

<?php

// array for JSON response
$response = array();

// check for required fields
if (isset($_POST['driver'], $_POST['licencenum'], $_POST['officer'], $_POST['speed'] , $_POST['fine'],$_POST['category'])){

    $driver = $_POST['driver'];
 $licencenum = $_POST['licencenum'];
 $officer = $_POST['officer'];
    $speed = $_POST['speed'];
    $fine = $_POST['fine'];
    $category = $_POST['category'];


    // include db connect class
    require_once __DIR__ . '/db_connect.php';

    // connecting to db
    $db = new DB_CONNECT();

    // mysql inserting a new row
$result = mysql_query("INSERT INTO fineregister(driver,licencenum,officer,speed,fine,category) VALUES   ('$driver','$licencenum','$officer','$speed','$fine',      '$category')");

    // check if row inserted or not
 if ($result) {
    // successfully inserted into database
    $response["success"] = 1;
    $response["message"] = "Speed Ticket Successfully Registered.";

    // echoing JSON response
    echo json_encode($response);
    } else {
    // failed to insert row
    $response["success"] = 0;
    $response["message"] = "Oops! An error occurred.";

    // echoing JSON response
    echo json_encode($response);
 }
} else {
// required field is missing
$response["success"] = 0;
$response["message"] = "Required field(s) is missing";

// echoing JSON response
echo json_encode($response);
}
?>

还有我的错误:

08-05 09:53:03.321: W/System.err(3072): org.json.JSONException: End of input at character 0 of 08-05 09:53:03.321: W/System.err(3072): at org.json.JSONTokener.syntaxError(JSONTokener.java:450) 08-05 09:53:03.321: W/System.err(3072): at org.json.JSONTokener.nextValue(JSONTokener.java:97) 08-05 09:53:03.331: W/System.err(3072): at org.json.JSONArray.(JSONArray.java:92) 08-05 09:53:03.331: W/System.err(3072): at org.json.JSONArray.(JSONArray.java:108) 08-05 09:53:03.331: W/System.err(3072): at com.lta.fine.JSONParser.makeHttpRequest(JSONParser.java:60) 08-05 09:53:03.341: W/System.err(3072): at com.lta.fine.MainActivity$CreateNewFine.doInBackground(MainActivity.java:191) 08-05 09:53:03.341: W/System.err(3072): at com.lta.fine.MainActivity$CreateNewFine.doInBackground(MainActivity.java:1) 08-05 09:53:03.351: W/System.err(3072): at android.os.AsyncTask$2.call(AsyncTask.java:288) 08-05 09:53:03.351: W/System.err(3072): at java.util.concurrent.FutureTask.run(FutureTask.java:237) 08-05 09:53:03.361: W/System.err(3072): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231) 08-05 09:53:03.361: W/System.err(3072): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112) 08-05 09:53:03.361: W/System.err(3072): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587) 08-05 09:53:03.361: W/System.err(3072): at java.lang.Thread.run(Thread.java:841) 08-05 09:53:03.361: E/Buffer Error(3072): Error converting result java.lang.NullPointerException: lock == null 08-05 09:53:03.371: E/JSON Parser(3072): Error parsing data org.json.JSONException: End of input at character 0 of

Answer 1

org.json.JSONException: End of input at character 0

通常意味着您没有获得任何 JSON。您将需要调试您的应用以找出原因。

同时我会给你一些建议:

PHP

• 不确定 INSERT 是否成功，但我注意到您没有使用 $db 变量。
• 您愿意使用已弃用的 mysql 扩展进行 sql 注入(inject)
• 你应该在你的 json 中使用 boolean
• 回显最后的 json。

---

<?php

// array for JSON response
$response = array();

// check for required fields
if (isset($_POST['driver'], $_POST['licencenum'], $_POST['officer'], $_POST['speed'] , $_POST['fine'],$_POST['category'])){

    $driver = $_POST['driver'];
    $licencenum = $_POST['licencenum'];
    $officer = $_POST['officer'];
    $speed = $_POST['speed'];
    $fine = $_POST['fine'];
    $category = $_POST['category'];


    // include db connect class
    require_once __DIR__ . '/db_connect.php';

    // connecting to db
    $db = new DB_CONNECT();

    // mysql inserting a new row
    $result = mysql_query("INSERT INTO fineregister(driver,licencenum,officer,speed,fine,category) VALUES   ('$driver','$licencenum','$officer','$speed','$fine','$category')");

    // check if row inserted or not
    if ($result) {
        // successfully inserted into database
        $response["success"] = true;
        $response["message"] = "Speed Ticket Successfully Registered.";
        // echoing JSON response
    } else {
        // failed to insert row
        $response["success"] = false;
        $response["message"] = "Oops! An error occurred.";
    }
} else {
    // required field is missing
    $response["success"] = false;
    $response["message"] = "Required field(s) is missing";
}
    // echoing JSON response
    echo json_encode($response);
?>

Java:

• 我看到您的方法返回了一个 JSONObject，它已经限制了您从解析数组。而是将 json 作为字符串返回，然后对其进行解析。
• 你在方法内部解析数据，这使得它更难以使用。
• 我认为几乎没有理由使用 GET 你不妨把它分开功能。

---

public String makeHttpRequest(String url, List<NameValuePair> params) 
{
    InputStream is = null;
    String json = "";

    // Making HTTP request
    try {
        DefaultHttpClient httpClient = new DefaultHttpClient();
        HttpPost httpPost = new HttpPost(url);
        httpPost.setEntity(new UrlEncodedFormEntity(params));

        HttpResponse httpResponse = httpClient.execute(httpPost);
        HttpEntity httpEntity = httpResponse.getEntity();
        is = httpEntity.getContent();


    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    } catch (ClientProtocolException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }

    try {
        BufferedReader reader = new BufferedReader(new InputStreamReader(
                is, "iso-8859-1"), 8);
        StringBuilder sb = new StringBuilder();
        String line = null;
        while ((line = reader.readLine()) != null) {
            sb.append(line + "\n");
        }
        is.close();

        json = sb.toString();
    } catch (Exception e) {
        Log.e("Buffer Error", "Error converting result " + e.toString());
    }


    // return JSON String
    return json;

}

异步任务

protected String doInBackground(String... args) {
    String driver = inputDriver.getText().toString();
    String licencenum = inputLicence.getText().toString();
    String officer = inputOfficer.getText().toString();
    String speed = inputSpeed.getText().toString();
    String fine= FineAppl.getText().toString();
    String category = inputCategory.getText().toString();


    // Building Parameters
    List<NameValuePair> params = new ArrayList<NameValuePair>();
    params.add(new BasicNameValuePair("driver", driver));
    params.add(new BasicNameValuePair("licencenum", licencenum));
    params.add(new BasicNameValuePair("officer", officer));
    params.add(new BasicNameValuePair("speed", speed));
    params.add(new BasicNameValuePair("fine", fine));
    params.add(new BasicNameValuePair("category", category));

    // getting JSON String
    // Note that create product url accepts POST method
    String json = jsonParser.makeHttpRequest(url_create_fine, params);

    return json;
}



protected void onPostExecute(String json) {
    // dismiss the dialog once done
    pDialog.dismiss();
    Log.d("mylog", "json = " + json);
    //parse here
}

在 doInbackground 中执行请求并将结果传递给 post execute，在那里记录 json 对象，如果您在日志中得到任何内容，就可以开始解析。使用 boolean 值会更容易。

try {
    JSONObject jsonData = new JSONObject(json);
    Boolean success = jsonData.getBoolean("success");
    String message = jsonData.getString("message");

    if (success) {
    //success
    } else {
    // failed to Register Fine
    }
} catch (JSONException e) {
    e.printStackTrace();
}